1 week old spitting up a lot

Just in the last day or two, my 1 week old has been spitting up a lot, i know a little bit is super common. But it’s like sometimes it seems like he throws up everything he just ate. It’s always milk, but it’s like every time i feed him within the next 30 minutes. He doesn’t seem phased or bothered by it, and he still pooping a lot. His poop is mustardy yellow and seedy. I’m just worried he’s not getting enough. I have his next doctors appointment in a week, but should i call the doctor sooner?